Frame having a central backbone and opposing skins

ABSTRACT

The present invention is directed to an improved frame construction for transmitting in-plane and out-of-plane loads between a plurality of components and maintaining the components in spacial relation. The frame is comprised of a plurality of node members for interconnection with the components and a plurality of beams and skin members interconnecting the node members. The beams include two channels on opposing sides for receiving the outer edges of the skin members. Preferably, the node members and beams form a perimeter channel that extends substantially around the entire perimeter of the frame and the skin members are secured thereto.

FIELD OF THE INVENTION

This invention relates generally to frames for interconnecting twopoints and transmitting in-plane and out-of-plane loads therebetween.More particularly, the invention is directed to a bicycle frame andcomponents.

BACKGROUND OF THE INVENTION

Conventional bicycle frames use metal tubes welded into closedframeworks to interconnect the components (front fork/handlebarassembly, seat, crankset, rear wheel) and transmit the loadstherebetween. The metal tubes keep the components in spacial relation,i.e., they maintain the components relative proximity. Moreover, themetal tubes bear the in-plane and out-of-plane loads between thecomponents.

The traditional bicycle frame comprises: a top tube connected at itsfront end to the top of the relatively short head tube, and extendinggenerally horizontally backward to the top of the seat tube; a down tubeconnected at the front end to the bottom of the head tube and extendingdownwardly and rearwardly to the bottom bracket where the seat tube andthe down tube are connected; and pairs of chain stays and rear wheelstays extending backward to dropouts which support the rear wheel axle.This conventional frame design is called the "diamond" frame, becausewhen viewed from the side, the top tube, down tube, chain stays, andrear wheel stays enclose a diamond-shaped space.

Such frames require that the entire frame be re-designed for thedifferent size frames required to accommodate riders of differentheights. This includes determining the tube lengths needed for theproper spacing of the bicycle component, cutting the tubes accordingly,determining the tube joint angles, and accordingly welding or brazingthe tubes together. This method is time consuming and costly, both interms of design and manufacturing complexity. Therefore, it is desiredto have a frame that is easier to manufacture, particularly whenmanufacturing different frame sizes.

Furthermore, conventional tube frames are relatively heavy, since theyare formed from the extrusion or rolling and seaming of metal alloys.Finally, conventional tube frames are limited in terms of aerodynamicimprovements, as they are restricted to the use of tubes of generallycircular cross-sections.

It is known to manufacture bicycle frames entirely from compositematerials such as in U.S. Pat. No. 4,889,355 to Trimble, wherein theframe is constructed using an internal pressure mold to form compositetubes. However, this manufacturing method does not take advantage of theuse of different materials or appropriate configuration to bear thedifferent loads to which a bicycle frame is subject to in use.

Another example of a frame known in the art is seen in U.S. Pat. No.5,456,481 to Allsop, et al., which discloses a frame having right andleft body units which mate directly to each other. All structuralelements of the frame are formed from the same material. Again, thismanufacturing method does not take advantage of the use of differentmaterials or appropriate configuration to bear the different loads towhich a bicycle frame is subject to in use. Therefore, there is a needfor a bicycle frame having separate structural elements manufacturedsuch that the various elements take advantage of the differentproperties of the materials or configurations, thus permitting the mostefficient possible frame for all expected loads.

In the conventional bicycle frame design, the seat support is designedintegral to the seat tube: the top of the seat tube is notched, and thenotch is provided with a screw clamp. The inner diameter of the seattube is selected to slideably receive a standard seat post, and theclamp is tightened to secure the seat post in the desired verticalposition. This conventional seat support design requires that the seattube be bored to a very precise diameter so that it will accept the seatpost, while at the same time not being so large as to requiresignificant distortion of the seat tube's cross-sectional shape when thescrew clamp is tightened. Furthermore, the use of a single screw clampprovides only a single point of support for the seat post. The insidediameter of the seat tube is by necessity larger than the outsidediameter of the seat post, therefore there will be play between the seatpost and the part of the seat tube below the clamp. In this situation,the single support leaves the seat post free to deflect or vibratewithin the seat post tube in response to moments around that point ofsupport. Therefore, it is desired to provide a seat support assemblywhich does not require precise machining, and which provides more than asingle point of positive support for the seat post.

Thus, the need exists for a strong, lightweight bicycle frame which iseasy to manufacture, which uses different materials in different partsof the frame to most effectively take advantage of the properties ofthose materials, which can easily accommodate different size framesusing standard components, and having an improved seat support assembly.

SUMMARY OF THE INVENTION

The present invention is directed to an improved frame construction fortransmitting in-plane and out-of-plane loads between a plurality ofcomponents and maintaining the components in spacial relation. The frameis comprised of a plurality of node members for interconnection with thecomponents and beams and skin members interconnecting the node members.The beams include two channels on opposing sides for receiving the outeredges of the skin members. Preferably, the node members and beams form aperimeter channel that extends substantially around the entire perimeterof the frame and the skin members are secured thereto.

In one embodiment, the present invention is a bicycle frame having acentral backbone with outer skins attached to both sides of thebackbone. The central backbone is comprised of node members forinterfacing with the bicycle components. More particularly, the frameincludes a first node member that includes bearing races for receivingthe steering/front fork assembly and a second node member for receivingthe crank assembly. The frame further comprises a first plurality ofbeams interconnecting the first and second node members. The beamsinclude two opposing channels for receiving the outer skins. Preferably,the central backbone is further comprised of a third node member for theseat assembly and a second plurality of beams extending from the seatassembly node to the first plurality of beams.

In this embodiment, the present invention provides a bicycle framehaving a torque tube and a seat mast. The torque tube extends downwardand backward from a front fork/steering support node member to a crankassembly/bottom bracket node member. The seat mast extends upward andbackward from the torque tube and terminates at the seat supportassembly node member. The frame is comprised of a backbone includingnodes at the front fork/steering support region, the crankassembly/bottom bracket region and the seat support region and aplurality of beams interconnecting the nodes having opposing channelstherein. The frame is further comprised of opposing skin members thatare received in the beam channels. Preferably, the node members alsoinclude channels to form a perimeter channel that extends substantiallyaround the entire frame for receiving the outer edges of the skinmembers.

The backbone may be manufactured as a single piece, out of varioussuitable materials and by various suitable processes. For example, thebackbone may be formed by: CNC machined or cast metal or injectionmolded plastic.

The backbone may alternatively be constructed from several distinctpieces joined together. Separate node members for the steering support,seat support, and bottom bracket are made separately and connected viabeams. Preferably, the connections between the nodes and beams aredesigned to overlap. The overlap of material provides a larger surfacearea for the joint, resulting in a stronger mechanical connection.

Each skin may be of a one-piece construction, or of multiple components.In a preferred embodiment, the skin members comprise torque tube skinmembers and seat mast skin members. The torque tube skin members providean exterior sheath for the steering support region, the torque tube, andthe bottom bracket region. The seat mast skin members provide a sheathfor the seat mast, which extends from the torque tube to the seatsupport assembly. Most preferably, the seat mast skin members includecurved flaps at the lower ends, which conform to and wrap around thetorque tube, providing a large surface-to-surface connection between theskin pieces. Alternatively, the seat mast skin pieces may simplyterminate at the torque tube, providing a simple edge-to-surfaceconnection.

The skins may be affixed in the perimeter channel of the backbone byvarious appropriate techniques according to the materials used. Mostpreferably, an epoxy adhesive is used to adhere the skins to the beamchannels.

The backbone and skin members may be made from a variety of suitablestructural materials. Most preferably, the backbone is made fromaluminum alloy 356, and the skin members are made from a carbonfiber/epoxy composite.

The present invention is also directed to a seat support assemblycomprising an arm and at least one band clamp. The band clamp tightensaround a standard seat post to frictionally engage the same against thearm, thus providing a lightweight, positive support and preventingvertical and rotational motion as well as vibration of the seat post.

BRIEF DESCRIPTION OF THE DRAWING

Preferred features of the present invention are disclosed in theaccompanying drawings, wherein similar reference characters denotesimilar elements throughout the several views, and wherein:

FIG. 1 is a perspective view of a bicycle frame in accordance with thisinvention;

FIG. 2 is an exploded perspective of the frame of this invention;

FIG. 3 is a perspective view of the backbone;

FIG. 4 is a perspective view of the left side torque tube skin;

FIG. 5 is a perspective view of the right side seat mast skin;

FIG. 6 is a perspective view of the seat support assembly;

FIG. 7 is a perspective view of the center node;

FIG. 8 is a perspective view of the steering support node;

FIG. 8A is a perspective view of a second embodiment of the steeringsupport node;

FIG. 9 is a perspective view of a beam member;

FIG. 10 is a perspective view of the bottom bracket node;

FIG. 11 is an enlarged sectional view of the torque tube taken alongline 11--11 of FIG. 1;

FIG. 12 is an exploded perspective of a swing arm according to thepresent invention;

FIG. 13 is an exploded perspective of a second embodiment of the swingarm according to the present invention;

FIG. 14 is an exploded perspective of a pedal crank according to thepresent invention;

FIG. 15 is an exploded perspective of a second embodiment of the pedalcrank according to the present invention;

FIG. 16 is a plan view of a wheel according to the present invention;and

FIG. 17 is an enlarged sectional view of the wheel spoke taken alongline 17--17 of FIG. 16.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

FIG. 1 illustrates bicycle frame 10 in accordance with the presentinvention. The bicycle frame 10 is formed of a negative space framedesign, i.e., the frame does not include a top tube. The frame consistsof a torque tube 12, which extends from the steering support region 14to the bottom bracket region 16 and a seat mast 18, which is attached tothe torque tube and extends rearward and upward therefrom to seatsupport assembly 56. Preferably, the seat mast 18 is connected to thetorque tube 12 between the steering support region 14 and the bottombracket region 16.

The frame of the present invention accepts and interconnects componentsthat are available in the industry, but the components do not constitutepart of the invention. For example, the steering support 14 accepts aCannondale HEADSHOK™ steering assembly or standard handlebar and frontfork/wheel assembly, the seat support assembly 56 accepts a seat mountedon a standard seat post, and the bottom bracket 16 accepts a cranksetand a rear swing arm/wheel assembly. These components are known in theart and, therefore, they are not illustrated in the figures.

As seen in the exploded view of FIG. 2, the bicycle frame is comprisedof a central backbone 40 and skin members 30, 32, 34 and 36. The frameis constructed by joining the left torque tube skin member 30, left seatmast skin member 34, right torque tube skin member 32, and right seatmast skin member 36 to the central backbone 40 by securing the skinmembers to a perimeter channel formed in the backbone 40.

Referring to FIG. 3, the central backbone 40 comprises four nodalelements (center node 54, seat support assembly 56, steering supportnode 50, and bottom bracket assembly 52) connected by the various beams41-46. The nodes 50, 52, 54 and 56 provide attachment locations for thevarious bike components that must be interconnected via a structuralframe that bears the in-plane and torsional loads. This node-and-beamdesign minimizes the parts required for different sized frames byallowing the use of common nodes for all frames, simply using beams ofdifferent lengths to produce frames of the desired size. The backbone 40is preferably an assembly of several parts joined together, as will beexplained in more detail below. However, it is evident to one skilled inthe art that the backbone could also be constructed as a singlemonolithic part.

The backbone of the present invention may be formed from suitablestructural materials by the appropriate process. For example, it may be:cast or CNC machined from a light metal such as aluminum, titanium, ormagnesium; injection or compression molded plastic; or molded fiberreinforced plastic such as fiberglass. In the preferred embodiment, thebackbone is formed from cast aluminum, such as AL-365. Although thebackbone of the illustrated embodiment incorporates a novel seat supportassembly 56, it is evident to one skilled in the art that it could alsoincorporate a conventional tube-type seat support.

Loads are applied to the frame through the component node members. Forexample, forces from rider mass are applied through the seat supportassembly 56, forces from rider steering and from the front wheel throughsteering support node 50, forces from the rear shock through the centernode 22, and forces from pedaling and from the rear wheel through bottombracket assembly 16. The backbone efficiently distributes and resistsin-plane loads, through the placement of the interconnecting beams andcross-bracing trusses (FIG. 8A).

FIG. 6 illustrates the seat support assembly 56 according to thisinvention. The seat support assembly consists of a pair of band clamps60, 62 whose support is incorporated into the seat assembly node 57 ofthe backbone. This design allows ease of manufacture by eliminating theboring and reaming operations required to manufacture conventional seatsupport assemblies, and the associated difficulties of matingdimensional tolerances of the seat support assembly to the outsidediameter of the seat posts.

The seat support assembly 56 is comprised of a plate 81 with beammembers 86 and 88 extending rearwardly from the plate 81 to form part ofthe seat support node 57. A pair of spaced apart support arms 82 extendfrom the plate 81 from the opposite side of the beams 86 and 88.Extending from the arms 82 are a plurality of fingers 83. Preferably,each arm 82 has two spaced-apart pairs of fingers 83. Each pair offingers 83 form a semicircle for abutting against the seat post (notshown) and supporting the same.

The band clamps 60 and 62 extend from the arms 82 to loop around andsecure the bike seat post. Each end of the band clamps 60 and 62includes a loop for receiving a barrel nut 84. Adjustment of the bandclamps 60 and 62 is accomplished using the barrel nuts 84, which can bedrawn together using a threaded bolt (not illustrated). The band clamps60 and 62 are preferably made from stainless steel.

The seat support assembly 56 of the present invention uses a band clampand preferably two band clamps 60 and 62 to provide substantially moresupport for the seat post than a conventional screw clamp device,without introducing any additional stress into the frame itself. Bytightening at least one band clamp, the seat post is supported by a widearea. With more than one band clamp, the seat post is supported at twospaced-apart locations along its length, effectively preventingdeflection and vibration of seat post within the support assembly 56.

Furthermore, the seat support assembly 56 of the present inventionefficiently provides material at the locations where support is actuallybeing given to the seat post. That is, the band clamps 60 and 62 alongwith supporting fingers 83 provide a secure attachment for the seat postand are light weight.

The center node 54 of the backbone 40 is illustrated in FIG. 7. Thecenter node 54 interconnects the seat mast 18 and the torque tube 12.The center node 54 is comprised of upwardly extending arms 90 and 92 tojoin cooperatively with the seat mast beams 45 and 46. Longitudinallyextending arms 94 and 96 as well as lower corner point 98 are providedto join cooperatively with the torque tube beams 40, 43, 42, and 44. Theupwardly extending arms 90 and 92 are provided with channels 91 and 93which are designed to accept the side edges of the seat mast skins 34and 36. Preferably, the lower corner point 98 is configured so as toprovide channels having widths approximately twice that of the otherchannels generally. The double-width channels accept both theintermediate part of the bottom edge of the torque tube skins 30, 32 andthe bottom edges of the curved flaps 64, 66 of the seat mast skinpieces.

The center node 54 also includes a rear shock mounting flange 100 behindthe upwardly extending arm 92. The rear shock mounting flange 100 isprovided with a through bore 102 to provide an attachment point for therear shock absorber (not illustrated). The other end of the shockabsorber is secured to the rear swing arm to dampen shocks to the rearwheel. In the most preferred embodiment, the shock mounting flange 100is located at the point where the upwardly extending arm 92 andlongitudinally extending arm 96 meet. It is evident to one skilled inthe art that the location of the shock mounting flange 100 may beadjusted upwards along arm 92 or downwards along arm 96.

The steering support node 50 is illustrated in FIG. 8. It consists ofupper and lower bearing supports 110 and 112 respectively and verticalsupport members 114 and 116. Arms 118 and 120 extend outward anddownwardly from the steering support node 50 and provide cooperativecoupling for the torque tube beams 41 and 42. The bearing supports 110and 112 provide the interface between the frame and the steeringcomponents and front fork/wheel. Thus, the function of the steeringsupport node 50 is similar to that of the head tube of a traditionalframe.

The arms 118 and 119 and the vertical support member 114 includeopposing channels 120 and 122 for receiving the edges and ends of thetorque tube skins 30 and 32.

Referring now to FIG. 8A, a second embodiment of the steering supportnode 50 is disclosed. This embodiment is substantially similar to thefirst embodiment shown in FIG. 8, but is further comprised of a trussmember 117 extending between arm members 118 and 119 for additionalstructural strength and stiffness.

The bottom bracket node 52 is illustrated in FIG. 9. The pivot support136 is provided for support of the rear swing arm. The pedal spindlesupport 134 is provided for mounting of the crankset. The bottom bracketnode 52 has arms 130 and 132 extending outwardly and upwardly to providecooperative joining with the lower torque tube beams 43 and 44respectively. The bottom bracket node 54 also preferably includes aperimeter channel 138 to accept the edge of the lower portion of thetorque tube skins 30 and 32.

Having separately described the individual nodes 50, 52, 54 and 57 ofthe backbone, the construction of the unified backbone 40 can now beexplained in detail with reference to FIG. 3. Preferably, the backbonenodes 50, 52, 54 and 57 are formed separately and joined via a pluralityof beams 41, 42, 43, 44, 45 and 46. To improve the strength of theconnections between the backbone components (nodes and beams), the nodesand beams are designed to overlap at connection sections, rather than tosimply abut each other. For example, the arm 123 of the individualbackbone beam member 43 seen in FIG. 10 overlaps and forms a continuousbeam with arm 130 of bottom bracket assembly 50, seen in FIG. 9. Moreparticularly, the backbone 40 is comprised of opposing peripheralchannels that extend about substantially the entire periphery of thebackbone 40 for receiving the frame skin members 30, 32, 34 and 36. Theperipheral channels are formed of a vertical wall member, for example,123B, extending perpendicularly between two parallel wall members, forexample 123A and 123C. In the overlap sections, one of the parallel wallmembers is part of a node arm, for example 130C, and the other parallelwall member is formed by the beam, for example 123A. This overlap ofparts contributes to the strength of the joint between the parts.

This mechanical overlap of the backbone pieces, together with the factthat the various pieces of the backbone are all positively affixed tothe skins, provides a very strong overall frame system. Therefore, it isnot necessary that the backbone pieces be positively affixed to eachother. However, if the backbone pieces are affixed to each other, thelarge contact surface area in the joint will result in a strongmechanical connection. The various parts of the backbone may be joinedto each other by sonic welding, conventional welding, brazing,adhesives, mechanical fasteners, or any other techniques appropriate tothe materials used.

Referring now to FIGS. 4 and 5, a left torque tube skin member 30 and aright seat-mast skin member 36, respectively, are shown. The skinmembers 30, 32, 34 and 36 consist of outer edges designed to fit intothe channels that extend substantially around the perimeter of thebackbone 40. In the preferred frame, the backbone is substantiallyenclosed by the skin members, with the exception of the outer flange ofthe backbone. The skin members provide in-plane and out-of-planestructural stiffness for the frame as well as improve the aerodynamicsof the frame and advantageously reduce the risk of the accidentalsnagging of objects such as branches, etc. in the trusswork of thebackbone.

The left skin and right skin of the preferred bicycle frame 10 are eachformed from multiple members, i.e., the torque tube skin members 30 and32 and the seat mast skin members 34 and 36. The torque tube skinmembers 30 and 32 provide an exterior sheathing for the torque tube 12.Similarly, the seat mast skin members 34 and 36 provide a sheathing forthe seat mast 18. However, it is evident to one skilled in the art thatthe skins may also be formed as a single piece for each side.

In the preferred embodiment, the torque tube skin members 30 and 32 havea steering support region 72, a bottom bracket region 64 and anintermediate region 70 extending therebetween. The bottom bracket region64 is provided with openings 66 and 68 to permit the fittings for thecrankset and rear swing arm, respectively. The steering support region72 substantially encloses the steering support node 50. The intermediateregion 70 provides axial and torsional stiffness between the bottombracket region 64 and the steering support region 72.

FIG. 11 provides a cross-sectional view of the torque tube 12, includinga detailed view of the backbone-to-skin joint. Preferably, the skinmembers 30, 32 are generally "C" shaped in cross-section, and are thinrelative to the overall cross-sectional diameter of the torque tube. Atthis location in the frame, the backbone comprises the beams 41 and 42.The beams preferably include two parallel wall members and aperpendicular wall member therebetween such that they are generally "I"shaped in cross-section, providing a perimeter channel on both sides, toaccept the edges of the skins. The edges of the skins may be joined tothe perimeter channel of the backbone by an adhesive, pressure fit,sonic welding, conventional welding, brazing, mechanical fasteners, orany other techniques appropriate to the materials used. The preferredjoining technique is to use an epoxy adhesive joint.

The peripheral channels of the backbone effectively captures the outeredges and ends of the skin members, such that tensile loading of theskin-to-backbone attachment will be resisted by the material shearstrength of the skin and backbone. Moreover, the loading borne by theadhesive will be primarily shear loading in the plane of attachment. Forexample, referring to the attachment of skin 30 to beam 41, the upperedge 30A of the skin is effectively "captured" between the backboneflanges 41A and 41C. The adhesive joint covers the surface area ofcontact between the upper and lower surfaces of the skin member edges(30A) and the perimeter channel formed by the inner surfaces of thebackbone flanges (41A and 41C). Tensile loads on the adhesive joint willbe opposed by the bulk material of the skin and beam.

In the preferred embodiment, the seat mast skins 34 and 36 extend fromthe center node 54 to the seat support node 57. The seat mast skinmembers 34 and 36 are provided with curved flaps 64 and 66 respectively,which extend downwardly beyond where the seat mast 18 meets the torquetube 12. The curved flaps closely conform to, and wrap around, thetorque tube skin pieces 30 and 32. The bottom edges of the curved flaps64 and 66 fit into the double-width channel provided in the lower cornerpoint 98 of center node 54 as discussed above. The curved flaps providestructural bracing which strengthens the connection of the seat mast tothe torque tube. It is obvious to one skilled in the art, however, thatthe flaps could be reduced in size or omitted altogether while stillproviding an acceptably strong bond between the seat mast skin piecesand the torque tube skin pieces by other methods.

The skin members 30, 32, 34 and 36 may be manufactured from anyappropriate material such as fiber reinforced epoxy or plastic,injection-molded plastics, stamped or hydro-formed metals, or othersuitable materials and processes. Generally suitable materials have ahigh strength-to-weight ratio and high flex modulus.

As shown in FIGS. 4 and 5, the skin members may be formed with internalstiffening ribs 74 and 62. Stiffening ribs may be selectively providedat areas of high stress to provide additional axial stiffness, forexample rib 74, or for additional torsional stiffness, for example rib62. More particularly, it is contemplated that skin members formed fromplastics may be formed with one or more ribs to provide increasedstrength and stiffness.

Due to the fact that the skin members are all positively affixed to thebackbone, it is not necessary to provide a positive means of affixingthe various skin pieces on one side to each other. However, if it isdesired to positively affix the various skin members to each other, thiscould be accomplished by force fit, sonic welding, conventional welding,brazing, mechanical fasteners, adhesives, or any other techniquesappropriate to the materials used. For example, it is preferred that theseat mast skin members 34 and 36 are adhered to the torque tube skinmembers 30 and 32.

The modular design of the frame of the present invention permits the useof different materials for the backbone and the skin members, thusallowing a design which takes the best advantage of the materials chosenand the configurations of the components. As best seen in FIG. 2, thepreferred backbone is a generally planar structural element composedlargely of I-beams. Therefore, the backbone is particularly strong inresponse to in-plane loads, such as those resulting from rider weight,shocks from jumps, or even head-on collisions with objects. The skinmembers, preferably having "C" shaped cross-sections, contributestrength in response to in-plane and out-of-plane loads. Thus, the frameof the present invention allows for the backbone and the skin members tobe made from different materials to advantageously allow the overallframe to take the best advantage of the range of available structuralmaterials.

Referring now to FIGS. 12 and 13, another embodiment of a frameaccording to the present invention is shown. In this embodiment, theframe consists of a bicycle swing arm 150. The bicycle swing arm 150includes a plurality of nodes 152, 154 and 156 interconnected by beammembers 160, 162 and 164. The nodes 152 and 154 provide the interfacebetween the swing arm 150 and the back wheel and the node 156 providesthe interface for the swing arm 150 with a bicycle frame. Beam member160 interconnects node 156 with node 154, beam member 162 interconnectsnode 154 with node 152 and beam member 164 interconnects node 152 withnode 156.

The swing arm frame is further comprised of skin members 170 and 172.The skin members are interconnected into channels in the beam members160, 162 and 164. Post members 180 and 182 and member 184 are providedon the skin member 172 for attaching the rear brake assembly to theswing arm member 150. The bracket members 190 are provided on the skinmember 172 for attachment of the rear shock absorber to the swing arm150 to provide the dampening of the shocks to the rear wheel.

The swing arm frame member 150 disclosed is FIG. 13 is substantiallysimilar to that disclosed in FIG. 12. However, the frame member 150 isfurther comprised of truss members 161, 163 and 165 for interconnectingthe beam members and providing additional stiffness and structuralstability. The truss member 161 interconnects beam members 160 and 164,truss member 163 interconnects beam members 162 and 160 and truss member165 interconnects beam members 164 and 162.

Now referring to FIGS. 14 and 15, a further embodiment of a frame memberaccording to the present invention is disclosed as a pedal crank arm180. The pedal crank arm 180 is comprised of two nodes members 182 and184. The node member 182 interconnects the pedal crank arm 180 to thebicycle pedal and the node member 184 interconnects the pedal crank arm180 to the crank assembly. Interconnecting the node members 182 and 184are beam members 186 and 188. The frame is also comprised of two skinmembers 190 and 192 which are received in channels in the node members182 and 184 and beam members 186 and 188.

The pedal crank arm frame 180 shown in FIG. 15 is substantially similarto the one shown in FIG. 14 but is further comprised of truss members189 which interconnect the beam members 186 and 188 for additionalstrength and structural stiffness.

Referring now to FIGS. 16 and 17, another embodiment of a frameaccording to the present invention is shown. In this embodiment, theframe is a wheel 200, which is comprised of a rim node 202 and an axlehub node 204 and a plurality of spokes 206 interconnecting the same. Theframe is similarly comprised of a backbone comprised of nodes 202 and204 with a plurality of beams 208 and 210 having channels thereinextending between the nodes 202 and 204. The rim node 202 interconnectsthe wheel 200 with a tire and the axle hub node 204 interconnects thewheel 200 with a wheel axle. The wheel 200 is further comprised of twoskin members 212 and 214, which are received within the channels of thebeam members 208 and 210 to provide the frame structure.

The advantageous features of the frame of the present invention is notlimited to bicycles. Although the detailed description refers to theframe in the form of a bicycle frame and bicycle components, many otherapplications are readily apparent. Examples of other applicationsinclude, but are not limited to, motorized bicycles, motorcycles,wheelchairs and other human-powered vehicles, as well as structures thattransmit in-plane and out-of-plane loads between a plurality ofcomponents.

While specific embodiments of the invention have been described andshown in the drawings, further variations will be apparent to thoseskilled in the art, and the invention should not be construed as limitedto the specific forms shown and described. The scope of the invention isto be determined solely by the following claims.

What is claimed is:
 1. A frame for maintaining two components in spacialrelation, comprising:a) a first node member for interconnecting with afirst component, the first node member having first opposing nodechannels; b) a second node member for interconnecting with a secondcomponent; c) a first plurality of beam members extending between andinterconnected with the first and second node members the beam membershaving opposing channels; and d) a plurality of skin members extendingbetween the first and second node members, said skin members havingouter edges secured in the beam channels and node channels.
 2. The frameof claim 1 wherein the skin members are secured to opposing sides of thebeam members.
 3. The frame of claim 2 wherein the beam channels extendalong substantially the entire length of the beams.
 4. A frame formaintaining two components in spacial relation, comprising:a) a firstnode member for interconnecting with a first component; b) a second nodemember for interconnecting with a second component; c) a first pluralityof beam members extending between the first and second node members, thebeam members having opposing channels; d) a plurality of skin membersextending between the first and second node members, said skin membershaving outer edges secured in the beam channels on opposing sides of thebeam members; and e) the first and second node members include opposingnode channels for receiving outer edges of the skin members, such thatthe frame has beam and node channels that extend substantially aroundthe entire periphery of the frame.
 5. The frame of claim 2 wherein thebeam members are substantially I-shaped.
 6. The frame of claim 5 whereinthe cross-section of the skin members is substantially C-shaped, withthe edges of the C being secured in the beam channels.
 7. The frame ofclaim 6 wherein the skin members are substantially adhered to thechannels in the beam members.
 8. The frame of claim 1 further comprisingat least one truss member interconnecting at least two of the beammembers for providing additional structural stiffness.
 9. The frame ofclaim 1 wherein the node members further include a plurality of armmembers for engaging with the beam members.
 10. The frame of claim 7wherein the node members include a plurality of arms, the arms and thebeam members partially overlap to form an overlap section such thatoverlap channels are formed by a portion of the arms and a portion ofthe beam members in the overlap section.
 11. A frame for maintaining twocomponents in spacial relation, comprising:a) a first node member forinterconnecting with a first component and having a first channel formedtherein; b) a second node member for interconnecting with a secondcomponent and having a second channel formed therein; c) a first beammember extending between and interconnected with the first and secondnode members, the beam member having opposing channels; and d) aplurality of skin members extending between the first and second nodemembers, said skin members having outer edges secured in the beamchannels and the first and second node channels.
 12. The frame of claim11 wherein the skin members are secured to opposing sides of the beammember.
 13. The frame of claim 12 wherein the beam channels extend alongsubstantially the entire length of the beam.
 14. The frame of claim 11wherein the beam member is substantially I-shaped.
 15. The frame ofclaim 12 wherein the cross-section of the skin members is substantiallyC-shaped, with the edges of the C being secured in the beam channels.16. The frame of claim 15 wherein the skin members are substantiallyadhered to the channels in the beam member.
 17. The frame of claims 1 or11 wherein the first node member is comprised of a plurality of bearingraces for interconnecting with steering components for a bicycle and thesecond node member is comprised of means for attaching a crank assemblyfor a bicycle.
 18. The frame of claim 17 further comprising a third nodefor supporting a bicycle seat post and a second plurality of beammembers extending between the third node and the first beam members. 19.The frame of claim 18 further comprising a forth node member forsupporting one end of a bicycle rear shock, the forth node memberforming a junction between the first beam members and the second beammembers.
 20. The frame of claims 1 or 11 wherein the first node memberis comprised of means for pivotally connecting the frame to a bicycleframe and the second node member is comprised of means for attaching theframe to a bicycle wheel.
 21. A frame for maintaining two components inspacial relation, comprising:a first node member for interconnectingwith a first component;a) a second node member for interconnecting witha second component; b) a first beam member extending between the firstand second node members, the beam member having opposing channels; aplurality of skin members extending between the first and second nodemembers, said skin members having outer edges secured in the beamchannels;c) the first node member includes means for connecting theframe to a bicycle pedal; and d) the second node member includes meansfor connecting the frame to a bicycle crank assembly.
 22. The frame ofclaims 1 or 11 wherein the first node member is comprised of a wheel rimfor receiving a tire and the second node member is comprised of a wheelaxle hub for receiving a wheel axle.
 23. A frame assembly comprising:a)a backbone unit comprising a steering support region having a steeringsupport region channel therein, a seat support assembly region, a bottombracket region, a first plurality of beams extending from andinterconnecting the steering support region to the bottom bracketregion, and a second plurality of beam members extending from a pointbetween the ends of the first beam members to the seat support region,the first and second beam members having opposing channels therein; andb) opposing skin members having outer edges; wherein the skin membersare configured and dimensioned such that their outer edges fit into theopposing channels in the first and second beam members and in thesteering support region channel.
 24. The bicycle frame assembly of claim23, wherein the steering support region, the seat support region and thebottom bracket region are comprised of arm members for connecting to thebeam members.
 25. The bicycle frame assembly of claim 24, wherein theconnections between the arm members and beam members compriseoverlapping joints, thereby providing increased strength and contactingsurface area.
 26. The bicycle frame assembly of claim 23 wherein theskin members are comprised of torque tube skin members with outer edgesthat fit into the channels of the first beam members and seat mast skinmembers with outer edges that fit into the channels of the second beammembers.
 27. The bicycle frame assembly of claim 26, wherein one end ofthe seat mast skin members of a seat mast are provided with curved flapsthat are shaped to substantially conform to and wrap around the outsideof the torque tube skin members of a torque tube.
 28. The bicycle frameassembly of claim 23, further comprising means for affixing the edges ofthe skin members within the channels of the beam members.
 29. Thebicycle frame assembly of claim 28, wherein the means for affixingcomprises epoxy adhesive.
 30. A seat support assembly for attaching abicycle seat post to a bicycle frame and preventing vertical androtational motion of the seat post, comprising:a) a plate memberintegrally formed with the bicycle frame; b) at least one arm memberextending from the plate member for abutting the seat post; c) aplurality of fingers extending from the arm member for positioning theseat post; and d) at least one clamp formed substantially as a ringextending from the arm, the clamp looping around and frictionallyengaging the seat post to the fingers.
 31. The seat support assembly ofclaim 30 further comprising a second arm member being spaced apart fromthe first arm member and extending from the plate member for abuttingthe seat post and a second band clamp for looping around andfrictionally engaging the seat post.
 32. The seat support assembly ofclaim 31 further comprising a plurality of attachment members extendingfrom the opposite side of the plate member from the arm members forattaching the seat support assembly to the bicycle frame.
 33. The seatsupport assembly of claim 31 further comprising a plurality of fingermembers extending from each arm member to engage the surface of the seatpost.
 34. The seat support assembly of claim 30 further comprising meansfor tensioning the band clamp around the seat post.
 35. The seat supportassembly of claim 34 wherein the tensioning means is comprised of abarrel nut received in a loop in the end of the band clamp and a screwthreaded into the nut for tightening the clamp.
 36. The seat supportassembly of claim 31 further comprising means for tensioning the bandclamps around the seat post.
 37. The seat support assembly of claim 36wherein the tensioning means is comprised of a barrel nut received in aloop in the end of the band clamps and a screw threaded into the nut fortightening the clamps.